A Search For Better Health Topic 3: Control of Disease

1. A Search For Better HealthTopic 3: Control of Disease Biology in Focus, HSC Course Glenda Childrawi, Margaret Robson and Stephanie Hollis

2. DOT Point(s) • explain why cleanliness in food, water and personal hygiene practices assist in control of disease world.edu

3. Introduction Micro-organisms are everywhere around us and can easily enter our bodies through any body openings. Not all of these are disease-causing microorganisms, but in order to decrease the spread and growth of pathogenic micro-organisms, and hence control the incidence and spread of disease, it is important that hygienic practices are followed. www.setyoufreenews.com

4. Introduction Cleanliness in food, water, and hygiene practices all help to prevent the growth and transmission of pathogens and therefore help to control disease. www.personal.psu.edu

5. Hygiene Hygiene can be divided into two types— personal and community hygiene: Personal hygiene involves keeping our bodies and any openings on them clean to reduce the risk of pathogens entering our bodies, or transmission of these pathogens to others, thus causing disease. It also inhibits the build up of micro-organisms on our bodies. www.eyeonspain.com

6. Hygiene Personal hygiene involves the following: ■ Hands should always be washed with soap and water before preparing and eating food and after going to the toilet. ■ The body and hair should be regularly washed and teeth cleaned to prevent the build-up of pathogens (particularly bacteria) to numbers sufficient to cause disease. ■ You should always cough or sneeze into a handkerchief. www.humptybumptykids.com

7. Hygiene Community hygiene is important as it helps to prevent the build-up of pathogenic organisms in the community and reduces the spread of disease. When the infrastructure that supports and maintains community hygiene breaks down, there is a rapid spread of disease, as seen in the aftermath of the tsunami that hit South-East Asia in 2005. www.halcrow.com

8. Hygiene Community hygiene involves the following: • Sewage and garbage disposal, which is important as it reduces the risk of pathogen numbers increasing and spreading throughout the community, thus controlling disease. • Sterilisation and disinfection of equipment in hospitals, doctors’ surgeries, dentists and hairdressers/ barbers, which reduces the risk of the spread of pathogens from one person to another. • City planning, which reduces overcrowding and therefore reduces the risk of the transmission of diseases throughout the population—this is important in controlling disease. fortressaustralia.blogspot.com

9. Cleanliness in Food Many pathogens can be transferred from person to person, or environment to person, in food. For example, salmonellosis is a disease caused by bacteria called Salmonella and is transmitted in undercooked food, especially foods of animal origin. culturewav.es

10. Cleanliness in Food Hepatitis A is another disease that can be transmitted by eating foods that have been handled by somebody who has the disease. It can also be transmitted when uncooked shellfish that has grown in waters polluted with sewage is eaten. drinksplaza.blogspot.com

11. Cleanliness in Food The incidence of food-borne disease has increased due to the trend to eat out on a more regular basis or to consume more takeaway foods. Bacteria will multiply quickly in food if the conditions are right—availability of nutrients, correct temperature and availability of moisture. www.guardian.co.uk

12. Cleanliness in Food • In order to control the transmission of disease from food sources, guidelines that must be followed by food handlers have been introduced for storing, preparing and serving food. www.menufinder.co.uk

13. Cleanliness in Food Unfortunately, not all food handlers follow these regulations the way they should; this leads to a greater incidence of disease caused by ingestion of contaminated food.. www.emmaculatereflections.com

14. Cleanliness in Food Some of these guidelines are: ■ Hands should always be washed with soap before and during the preparation of different foods, especially after touching raw food. ■ Hair should be tied back and any cuts covered. ■ All utensils to be used should be washed in hot soapy water and rewashed before using for different foods. This prevents crosscontamination, and transmission of pathogens. ■ A system of using different-coloured chopping boards for different types of food is to be used, again to prevent cross-contamination. fortressaustralia.blogspot.com

15. Cleanliness in Food Some of these guidelines are: ■ Frozen foods are to be thawed in either the refrigerator or the microwave. The longer raw food is left at room temperature, the more quickly bacteria multiply and toxins may form (see Fig. 2.13). Avoid thawing foods on the bench. ■ Raw vegetables are to be thoroughly washed before preparation and eating. ■ Refrigerators are to be kept below 5°C with adequate air flowaround food to ensure an even temperature distribution. fortressaustralia.blogspot.com

16. Cleanliness in Food Some of these guidelines are: ■ Hot foods are to be kept above 60°C (i.e. ‘steaming’ hot). ■ Cooked foods that are reheated should be reheated rapidly until all parts of the food reach 75°C. ■ All chicken and mince-based foods such as hamburgers should be cooked thoroughly. ■ Foods should be covered before storage in the refrigerator, freezer, and cupboards to protect them from contamination. fortressaustralia.blogspot.com

17. Cleanliness in Food The more closely these procedures are followed when storing, preparing and serving food, the less chance there is of the microbes in the food multiplying and being transmitted to individuals consuming the food, thus controlling the occurrence and spread of food-borne diseases. www.eatdrink.com.au

18. Cleanliness in Water Domestic water quality must comply with strict standards and guidelines in order to reduce the incidence of disease. In Australia, governments establish these standards and the water is tested daily to ensure these standards are met. www.nhmrc.gov.au

19. Cleanliness in Water It is important that water quality is maintained in order to minimise the risk of pathogens multiplying and to reduce the risk of the transmission of pathogens in contaminated water. www.h2o2.com

20. Cleanliness in Water Water that has been contaminated with the faeces of animals could contain unsafe levels of pathogens such as the protozoans Cryptosporidium and Giardia, and if consumed may cause symptoms such as abdominal cramps, diarrhoea, nausea and vomiting. Cholera is a potentially fatal disease that is transmitted in water that has been contaminated with untreated sewage. www.abc.net.au

21. Cleanliness in Water The treatment of water to destroy pathogens and prevent their further multiplication will reduce transmission of disease and is very important in the successful control of disease. www.sawater.com.au

22. Activity Students to watch video: http://youtu.be/AkSJF45uT9g fortressaustralia.blogspot.com

23. Homework -Students to complete DOT Point 2.5 Treatment of Drinking Water